Cement-Modified Backfills for Mechanically Stabilized EarthWalls with Built-In Facing

Abstract

A field study was undertaken to evaluate the performance of model geotextile-reinforced mechanically stabilized earth walls constructed using locally available marginal backfill soils without and with cement modification. Cyclic plate load tests were carried out on the constructed walls both at optimum moisture content and in fully wet conditions in the case of plain backfills and in fully wet condition for cement-modified backfills. The performance and utility of the proposed built-in soil cement facing with folded-back geotextile layers were also examined. The reduction in load-carrying capacity of walls upon wetting could be compensated by cement modification of marginal backfills while maintaining the pullout resistance of reinforcing layers with nominal variation in the flexibility of walls. The performance of model walls constructed using cement-modified marginal backfills is found to be even superior to the wall constructed using free draining sand backfill in terms of higher load-carrying capacity with reduced lateral facing deformations. It was observed that the geotextile-reinforcing layers in marginal backfills also facilitate the internal drainage.